High Alumina Cement
High Alumina Cement is manufactured by grinding clinkers of calcining bauxite (it’s an aluminium ore) and ordinary lime. In which the total amount of alumina content should not be lesser than 32% and it should maintain the ratio by weight of alumina to the lime between 0.85 to 1.30. Currently these high alumina cement are more popular in countries like United States and United Kingdom.
Advantages of High Alumina Cement:
1. The main advantage is that it can withstand high temperatures, so that it can be used in refractories, foundries and other workshops where high temperatures are involved.
2. The initial setting time is 3 hours than compared to that of ppc cement. And the final setting time of cement is 5 hours.
3. High Alumina Cement evolve great heat when setting so that these cements can be used in colder temperatures.
4. It is highly resistants to even concentrated acids and thereby it is widely used in chemical industries.
5. It sets fast and it attains a strength of 40 N/mm2 in just one day and 50 N/mm2 in three days.
Disadvantages of High Alumina Cement:
1. It is costly.
2. It evolves great heat and thereby it is not used in mass construction.
3. And moreover it should not get in contact with lime or ordinary PPC cement because it’s power gets reduced.